Rapid thermal analysis method for predicting nodular iron properties

Claim 1

A method of predicting metallurgical properties of a molten cast iron treated to form nodular cast iron on solidification, comprising the steps of: providing a heat of said molten cast iron, extracting from said heat a sample of said molten cast iron, allowing said sample to Cool from its molten state to a solid state, generating a cooling curve of said molten cast iron sample, said curve being obtained by continuously measuring and plotting the change in temperature with time of said sample of said iron while said sample of said iron is cooling from the molten to the solid state, dividing said cooling curve into characteristic curve segments indicative of the nucleation and growth reactions occurring during solidification of said sample of said iron, generating for each of said characteristic curve segments a respective family of like curve segments obtained in like manner from like cast iron samples of known composition and microstructure wherein each curve segment in each of said respective families is related to a known range of metallurgical properties, correlating said respective families of like curve segments to determine the largest range of metallurgical properties mutually related to each serial combination of said like curve segments of said respective families, comparing the shape of each characteristic curve segment with its respective family of like curve segments to determine the curve segment in each of said respective families most like each characteristic curve segment, serially combining said curve segments most like said characteristic curve segments, and determining from the serial correlation of the families of like curve segments the largest range of metallurgical properties possible for the serial combination of most like curve segments, said range indicating the metallurgical properties of said cast iron on solidification.

Claim 2

A method of predicting metallurgical properties of a molten cast iron treated to form nodular cast iron on solidification, comprising the steps of: providing a heat of said molten cast iron, extracting from said heat a sample of said molten cast iron, allowing said sample to Cool from its molten state to a solid state, generating a cooling curve of said molten cast iron sample, said curve being obtained by continuously measuring and plotting the change in temperature with time of said sample of said iron while said sample of said iron is cooling from the molten to the solid state, dividing said cooling curve into characteristic curve segments indicative of the nucleation and growth reactions occurring during solidification of said sample of said iron, generating for each of said characteristic curve segments a respective family of like curve segments obtained in like manner from like cast iron samples of known composition and microstructure wherein each curve segment in each of said respective families is related to a known range of metallurgical properties, correlating said respective families of like curve segments to determine the largest range of metallurgical properties mutually related to each serial combination of said like curve segments of said respective families, comparing the shape of each characteristic curve segment with its respective family of like curve segments to determine the curve segment in each of said respective families most like each characteristic curve segment, serially combining said curve segments most like said characteristic curve segments, and determining from the serial correlation of the families of like curve segments the largest range of metallurgical properties possible for the serial combination of most like curve segments, said range indicating the metallurgical properties of said cast iron on solidification.

Claim 3

A method of predicting microstructural and compositional properties of a molten cast iron treated to form nodular cast iron on solidification, comprising the steps of: providing a heat of said molten cast iron, extracting from said heat a sample of said molten cast iron, said sample having a thermal mass such as to cool from about 2, 300* F to 1,850* F in about 0.5 to 4 minutes, allowing said sample to cool from its molten state to a solid state, generating a cooling curve of said molten cast iron sample, said curve being obtained by continuously measuring and plotting the change in temperature with time of said sample of said iron while said sample of said iron is cooling from the molten to the solid state, dividing said cooling curve into characteristic curve segments indicative of the nucleation and growth reactions occurring during solidification of said sample of said iron, generating for each of said characteristic curve segments a respective family of like curve segments obtained in like manner from like cast iron samples of known composition and microstructure wherein each curve segment in each of said respective families is related to a known range of microstructural and compositional properties, correlating said respective families of like curve segments to determine the largest range of microstructural and compositional properties mutually related to each serial combination of said like curve segments of said respective families, comparing the shape of each characteristic curve segment with its respective family of like curve segments to determine the curve segment in each of said respective families most like each characteristic curve segment, serially combining said curve segments most like said characteristic curve segments, and determining from the serial correlation of the families of like curve segments the largest range of microstructural and compositional properties possible for the serial combination of most like curve segments, said range indicating the microstructural and compositional properties of said cast iron on solidification.

Claim 4

A method of predicting microstructural and compositional properties of a molten cast iron treated to form nodular cast iron on solidification, comprising the steps of: providing a heat of said molten cast iron, extracting from said heat a sample of said molten cast iron, said sample having a thermal mass such as to cool from about 2, 300* F to 1,850* F in about 0.5 to 4 minutes, allowing said sample to cool from its molten state to a solid state, generating a cooling curve of said molten cast iron sample, said curve being obtained by continuously measuring and plotting the change in temperature with time of said sample of said iron while said sample of said iron is cooling from the molten to the solid state, dividing said cooling curve into characteristic curve segments indicative of the nucleation and growth reactions occurring during solidification of said sample of said iron, generating for each of said characteristic curve segments a respective family of like curve segments obtained in like manner from like cast iron samples of known composition and microstructure wherein each curve segment in each of said respective families is related to a known range of microstructural and compositional properties, correlating said respective families of like curve segments to determine the largest range of microstructural and compositional properties mutually related to each serial combination of said like curve segments of said respective families, comparing the shape of each characteristic curve segment with its respective family of like curve segments to determine the curve segment in each of said respective families most like each characteristic curve segment, serially combining said curve segments most like said characteristic curve segments, and determining from the serial correlation of the families of like curve segments the largest range of microstructural and compositional properties possible for the serial combination of most like curve segments, said range indicating the microstructural and compositional properties of said cast iron on solidification.

Claim 5

A method of predicting the nodularity, carbon equivalent, and percent carbides of a molten cast iron treated to form nodular cast iron on solidification, comprising the steps of: providing a heat of said molten cast iron, extracting from said heat a sample of said molten cast iron, said sample having a thermal mass such as to cool from about 2, 300* F to 1,850* F in about 0.5 to 4 minutes, allowing said sample to cool from its molten state to a solid state, generating a cooling curve of said molten cast iron sample, said curve being obtained by continuously measuring and plotting the change in temperature with time of said sample of said iron while said sample of said iron is cooling from the molten to the solid state, dividing said cooling curve into characteristic curve segments indicative of the nucleation and growth reactions occurring during solidification of said sample of said iron, generating for each of said characteristic curve segments a respective family of like curve segments obtained in like manner from like cast iron samples of known nodularity, carbon equivalent, and percent carbides, wherein each curve segment in each of said respective families is related to a known range of nodularities, carbon equivalents, and percent carbides, correlating said respective families of like curve segments to determine the largest range of nodularities, carbon equivalents, and percent carbides mutually related to each serial combination of said like curve segments of said respective families, comparing the shape of each characteristic curve segment with its respective family of like curve segments to determine the curve segment in each of said respective families most like each characteristic curve segment, serially combining said curve segments most like said characteristic curve segments, and determining from the serial correlation of the families of like curve segments the largest range of nodularities, carbon equivalents, and percent carbides possible for the serial combination of most like curve segments, said range indicating the nodularity, carbon equivalent, and percent carbides of said cast iron on solidification.

Claim 6

A method of predicting the nodularity, carbon equivalent, and percent carbides of a molten cast iron treated to form nodular cast iron on solidification, comprising the steps of: providing a heat of said molten cast iron, extracting from said heat a sample of said molten cast iron, said sample having a thermal mass such as to cool from about 2, 300* F to 1,850* F in about 0.5 to 4 minutes, allowing said sample to cool from its molten state to a solid state, generating a cooling curve of said molten cast iron sample, said curve being obtained by continuously measuring and plotting the change in temperature with time of said sample of said iron while said sample of said iron is cooling from the molten to the solid state, dividing said cooling curve into characteristic curve segments indicative of the nucleation and growth reactions occurring during solidification of said sample of said iron, generating for each of said characteristic curve segments a respective family of like curve segments obtained in like manner from like cast iron samples of known nodularity, carbon equivalent, and percent carbides, wherein each curve segment in each of said respective families is related to a known range of nodularities, carbon equivalents, and percent carbides, correlating said respective families of like curve segments to determine the largest range of nodularities, carbon equivalents, and percent carbides mutually related to each serial combination of said like curve segments of said respective families, comparing the shape of each characteristic curve segment with its respective family of like curve segments to determine the curve segment in each of said respective families most like each characteristic curve segment, serially combining said curve segments most like said characteristic curve segments, and determining from the serial correlation of the families of like curve segments the largest range of nodularities, carbon equivalents, and percent carbides possible for the serial combination of most like curve segments, said range indicating the nodularity, carbon equivalent, and percent carbides of said cast iron on solidification.

Claim 7

A method of predicting the nodularity of a molten cast iron treated to form nodular cast iron on solidification, comprising the steps of: providing a heat of said molten cast iron, extracting from said heat a sample of said molten cast iron, said sample having a thermal mass such as to cool from about 2, 300* F to 1,850* F in about 0.5 to 4 minutes, allowing said sample to cool from its molten state to a solid state, generating a cooling curve of said molten cast iron sample, said curve being obtained by continuously measuring and plotting the change in temperature with time of said sample of said iron while said sample of said iron is cooling from the molten to the solid state, dividing said cooling curve into characteristic curve segments indicative of the nucleation and growth reactions occurring during solidification of said sample of said iron, generating for each of said characteristic curve segments a respective family of like curve segments obtained in like manner from like cast iron samples of known nodularity wherein each curve segment in each of said respective families is related to a known range of nodularties, correlating said respective families of like curve segments to determine the largest range of nodularities mutually related to each serial combination of said like curve segments of said respective families, comparing the shape of each characteristic curve segment with its respective family of like curve segments to determine the curve segment in each of said respective families most like each characteristic curve segment, serially combining said curve segments most like said characteristic curve segments, and determining from the serial correlation of the families of like curve segments the largest range of nodularities possible for the serial combination of most like curve segments, said range indicating the nodularity of said cast iron on solidification.

Claim 8

A method of predicting the nodularity of a molten cast iron treated to form nodular cast iron on solidification, comprising the steps of: providing a heat of said molten cast iron, extracting from said heat a sample of said molten cast iron, said sample having a thermal mass such as to cool from about 2, 300* F to 1,850* F in about 0.5 to 4 minutes, allowing said sample to cool from its molten state to a solid state, generating a cooling curve of said molten cast iron sample, said curve being obtained by continuously measuring and plotting the change in temperature with time of said sample of said iron while said sample of said iron is cooling from the molten to the solid state, dividing said cooling curve into characteristic curve segments indicative of the nucleation and growth reactions occurring during solidification of said sample of said iron, generating for each of said characteristic curve segments a respective family of like curve segments obtained in like manner from like cast iron samples of known nodularity wherein each curve segment in each of said respective families is related to a known range of nodularties, correlating said respective families of like curve segments to determine the largest range of nodularities mutually related to each serial combination of said like curve segments of said respective families, comparing the shape of each characteristic curve segment with its respective family of like curve segments to determine the curve segment in each of said respective families most like each characteristic curve segment, serially combining said curve segments most like said characteristic curve segments, and determining from the serial correlation of the families of like curve segments the largest range of nodularities possible for the serial combination of most like curve segments, said range indicating the nodularity of said cast iron on solidification.